Image: Frankie Roberto/Flickr
Another reason to grouse about airlines: though United Airlines will now let passengers "buy" inflight Wi-Fi with frequent flyer miles, the amount of miles necessary will vary based on demand. In other words, the surge pricing model has spread to the skies.On Thursday, United began testing a new web portal allowing mobile, tablet, and laptop users to trade miles for Internet access. Reuters reports that United plans to roll out the system to most domestic flights by early next year.The airline might be trying to downplay the fact that the more customers request the miles-for-Wi-Fi deal, the more miles you'll need to fork over. United's VP of Ecommerce and Marketing told Reuters that increased demand would cause Wi-Fi speeds to slow down, so for now, demand has to be kept at a reasonable level.Presumably, the flat dollar fee charged for Wi-FI will remain the same regardless of demand, though this is not explicitly stated. As of 2014, United was charging $2 per hour.This is effectively Uber's surge pricing used in a different context. (Surge pricing increases the cost of getting an Uber ride during peak times, like rush hour.) The surge pricing model, while a scourge for consumers, is still effective for businesses. Let's just hope it doesn't continue to spread.